Antibiotics are not an integral part of treating
CKD,
so if your vet prescribes them, you should ask why. Some CKD cats may need
them for other reasons, such as a urinary tract infection(UTIs), a kidney
infection or dental problems, but they are not normally given routinely to
a CKD cat. Commonly prescribed antibiotics for CKD cats include:
Most courses of
antibiotics last for 10-14 days. However, if your cat has a kidney
infection (pyelonephritis), a longer course is necessary, for 4-8 weeks.
Some UTIs also need a longer course of around four weeks.
Although most antibiotics start to show an effect
within 48 hours, once you begin a course of antibiotics, it is very
important that you complete the course. If you do not do so, the bacteria
may regroup and cause a stronger infection which has become resistant to
that antibiotic. If your cat reacts badly to an antibiotic, contact your
vet and discuss changing to another type.
Acidophilus is
a good choice for rebalancing gut bacteria -
Pet Education discusses this.
Effects of lactobacillus acidophilus DSM13241 as a probiotic in healthy
adult cats (2006) Marshall-Jones ZV, Baillon M-LA,Croft JM
& Butterwick RF American Journal of Veterinary Research67(6)
pp1005-1012 concluded that "administration of this probiotic results in
beneficial systemic and immunomodulatory effects in cats."
Culturelle contains lactobacillus. A typical feline dose
is half a capsule in the morning and half a capsule in the evening while
the cat is on antibiotics, but check with your vet.
Benebac is
designed especially for pets, and is available from
Revival Animal Health among others.
FortiFlora is a nutritional supplement for cats which contains a
probiotic, though it also contains vitamins, amino acids and iron. I
therefore think it is perhaps not the best choice of probiotic, but some
cats love it, so it can be helpful if added in small quantities to make
food or pills more tempting. It is available from
Entirely Pets.
Although Azodyl
is a form of probiotic, it is not given for the same reasons as probiotics
generally (see
Treatments), so should
not be given at the same time as
antibiotics; separate them by 6 hours.
Clavamox/Synulox (Amoxicillin and Clavulanate)
Clavamox, known
as Synulox or Noraclav in Europe, is a combination of two drugs, amoxicillin and
clavulanate, which work together to treat or prevent bacterial infections
in animals. Amoxicillin is an antibiotic in the penicillin family.
Clavulanate is an inhibitor of an enzyme produced by bacteria, which could
render the amoxicillin inactive if the clavulanate were not present. This
means Clavamox may kill bacteria which amoxicillin alone could not kill.
This antibiotic
is often prescribed for urinary tract infections in CKD cats. It tends to
be the antibiotic which most UK vets prescribe routinely for many
infections. I happen to like Synulox, not least because it comes in
flavoured pills in the UK which Harpsie would happily eat out of my hand.
But unfortunately it can cause stomach upset, vomiting and loss of
appetite in some cats. One of my other cats, Karma, just can't tolerate it
for more than a few days. Apparently it is not uncommon for cats to be
fine for a few days on this antibiotic but to then exhibit side effects
towards the end of the course. Giving food before you give the antibiotic may
help, but if not, contact your vet to see if you should switch to a
different antibiotic, but do not simply stop giving the Clavamox/Synulox
because this may make the infection return.
Mar Vista Vet has some information about
Clavamox (be sure to click on the additional link about amoxicillin).
Pet Place
also has some information about Clavamox (no need to register to read the
article, just click on Close at the bottom of the irritating pop-up).
Baytril (Enrofloxacin)
Baytril is an
extremely effective broad spectrum antibiotic (i.e. it works on a wide
range of bacteria) which belongs to the fluoroquinolone family. It is
particularly good for kidney infections, where it can reach bacteria deep
in the kidneys which less powerful antibiotics cannot touch. It saved
Harpsie's life on several occasions.
However, like
any antibiotic, Baytril has possible side effects. The most worrying one
with Baytril is that in certain rare cases it has caused retinal problems,
including blindness, if given to cats in high doses. Blindness has
reversed in some cases once the Baytril is stopped, but not in all.
Since the risk
of retinal problems appears to be linked to dosage (the issue did not
arise until the recommended dosage limits were dramatically increased), the official
recommended dose in
most countries is now 5 mg of Baytril per kg of bodyweight of the cat per
day. For the overwhelming majority of cats, this is a safe dosage. Having
said that, Dr I Jurk of
Tufts University Cummings School of Veterinary Medicine
(2003) mentions that although most cases of blindness have occurred
in cats given larger doses of 10-20mg/kg, one cat had received a dose of
only 4.6 mg/kg.
A kg is 2.2
lbs, so, for example, the maximum daily dose for a 10 lb cat is 22.5mg per
day, calculated as follows:
10lb cat = a
4.5kg cat x 5mg per kg = 22.5mg per day.
The recommended maximum course of treatment is 30 days (although Harpsie
was on a longer course a couple of times for his kidney infections with no problems). Baytril is given once daily; giving it more frequently actually reduces
its effectiveness.
Most people give Baytril in pill form, but it doesn't taste very nice, so
it is also available as a chewable tablet called Taste Tabs. There is an
injectable form of Baytril but it is only approved for dogs. Some people
have used it for cats, although there is a small risk of an abscess at the
injection site.
Baytril must not be given orally within two hours of products containing calcium
or aluminium (such as phosphorus binders)
or iron (such as Pet
Tinic), because they may inhibit absorption of the Baytril. Sucralfate must also be
give separately from Baytril for the same reason.
Drugs has some information about this.
Baytril may lower the seizure threshold, so may not be the best choice in
cats with a tendency to have seizures. Although Harpsie had epilepsy,
fortunately for us he never had any problems with Baytril.
Pet Place has some information about
Baytril (no need to register, just click Close at the bottom of the
annoying pop up).
Bayer, the manufacturer of Baytril, has
some
information on the risks of blindness in cats.
Dosage and duration of treatment is a
report from Bayer, the manufacturer of Baytril, on the recommended dosage
and length of treatment. It mentions that Baytril appears to be most
effective when it is given once daily.
US Food and Drug Administration
has a copy of a letter sent by Bayer to American vets outlining the risks
of blindness at high doses and recommending a maximum dose of 5mg per kg
bodyweight per day.
Antirobe (clindamycin)
belongs to the lincosamide family of antibiotics. It is approved for use
in dogs but is used off-label for cats. Antirobe is often prescribed for
dental problems because it is particularly good at killing anaerobic
bacteria which are commonly found in the mouth.
Like most
antibiotics, Antirobe may cause an upset stomach. It should be used with
caution in CKD cats - the normal dosage may need to be adjusted. The
manufacturers recommend that kidney and liver bloodwork should be checked
if Antirobe is given for longer than 30 days.
Convenia is an injectible antibiotic in the cephalosporin class which
was approved in Europe in 2006 and in the USA in 2008. It is approved in
the USA for the treatment of skin infections in dogs and cats and
urinary tract infections in dogs. In Europe it is approved
for these conditions but also for the treatment of urinary tract
infections in cats.
Convenia is only available as an injection. It lasts 14 days, so is
very convenient, particularly for cats who hate to be pilled.
Efficacy and safety of cefovecin for the
treatment of urinary tract infections in cats (2008)
Passmore CA, Sherington J, Stegemann MR Journal of Small Animal
Practice49(6) pp295-301 found that an injection of
Convenia was as effective as a 14 day course of cephalexin.
Most people I have heard from who have used Convenia were pleased with
it. My Ollie was given this for a urinary tract infection but his UTI
symptoms began to return about 10 days after the shot, so we switched
to Synulox, which seemed to work better for him.
However, like any antibiotic, Convenia has potential downsides.
Possible side effects commonly seen with antibiotics include lethargy, vomiting and diarrhoea. There
may also be skin irritation at the injection site.
Drugs reports on possible side
effects, some of which are quite severe, such as rare reports of
haemolytic anaemia or
pulmonary oedema.
If your cat does have a bad reaction, the fact that Convenia is so
long lasting becomes a disadvantage, because your cat's body remains
exposed to the drug. Convenia can remain
in the body for up to 65 days.
The European Medicines Agency
recommends that Convenia should be reserved for use in animals whose
conditions have not responded to or are not expected to respond to other
antibiotics.
Convenia has not been tested in cats with severe kidney problems, but
Drugs reports that some cats in a
safety study had mild elevations in BUN and creatinine levels after
using Convenia.
Famotidine (Pepcid AC) can interfere with antibiotics in the
cephalosporin family such as Convenia, so you should separate the two
treatments.
Firstly, I must emphasise that CKD is not usually a painful disease, so
does not normally require painkillers. However, a CKD cat may occasionally
require a painkiller, e.g. if the cat has
arthritis
or pancreatitis, or has
dental work or some other type of surgery done, or develops a
saddle thrombus.
Therefore it can be helpful to know about the various painkillers that may
be used in cats. This section covers the following:
It is easier to stop pain developing rather than trying to control it once
it has begun, so if for example your cat is about to have a dental, be
sure to discuss pain control with your vet in advance.
It can be rather difficult to find a suitable painkiller, because many
painkillers which work well for dogs and humans are not appropriate for
cats.
The Winn Feline Foundation is sponsoring
a study into pain in cats, Development of
outcome assessment instruments for chronic pain in cats, at the University
of Pennsylvania, which it is hoped will help develop suitable painkillers
in the future.
Unfortunately cats instinctively try to hide the
fact that they are in pain, and some of the
signs of pain in cats are
different to what you might expect, e.g. purring,
restlessness. Other possible signs include growling, avoiding
interactions, sleeping a lot or sitting in a hunched position. The
following links may help you determine if pain is a concern for your cat:
Pet Place has an overview of pain in cats (no need to register to read the article, just click on
Close at the bottom of the annoying pop-up).
Opiates
Opiates are narcotics, which means they belong to the same drug family as
morphine. These drugs are derived from the poppy and are the most
powerful painkillers.
Buprenorphine is a narcotic which is thirty times more potent than
morphine. Trade names include Buprenex
(USA) and Vetergesic (UK).
Buprenorphine should not be given orally because it is ineffective when
given in such a way. It can be given as an injection, but in cats it is commonly given in intrabuccal form, i.e. it is squirted
into the mouth towards the cheek. It is flavourless so most cats tolerate this
well. When given into the cheek, buprenorphine is absorbed through the mucus membrane and usually takes
effect quickly, within 30 minutes, with its effects lasting for eight
hours (although Colorado State University College of Veterinary Medicine
is currently researching a sustained release version of buprenorphine
which lasts up to three days). The usual dose is 0.01-0.03 mg/kg if given into the mouth, so a
10lb cat (4.55kg) would receive 0.046- 0.136 mg up to three times a
day. Since these are tricky amounts to calculate, many vets provide small
syringes containing the correct dose and you just gently squeeze the
contents into
your cat's mouth towards the cheek.
Most people I've heard from find buprenorphine extremely effective with few side
effects. The most common side effect is sedation and it may also slow
breathing. You may see dilated pupils.
It makes some cats purr more and become very affectionate, whilst other cats
become restless.
Buprenorphine is cleared by the liver so it tends to be a good choice for
CKD cats who need ongoing pain control. However, cats with CKD may
eliminate it more slowly, so discuss with your vet whether to lower the
dose. Be careful if you are using it with
cyproheptadine
(an appetite stimulant) because using both together may result in an
increased sedative effect.
Unfortunately buprenorphine can be expensive. Although the 5ml vials tend
to be cheaper, it is better to buy the 1ml vials because there is a
preservative added to the 5 ml vials which gives the medication an
unpleasant taste.
Viovet in the UK sells buprenorphine for
£14.12 for five 1ml vials.
Diamondback Drugs in the USA apparently
sell a two month supply of buprenorphine for under US$30.
Systemic update of buprenorphine by cats after oral
mucosal administration (2003) Robertson SA, Taylor PM & Sear JW
Veterinary Record152(22) pp675-8 found that administering
buprenorphine via the oral mucosal route was as effective as injecting it,
and the majority of owners preferred this method of administration.
The National Office of Animal Health
in the UK provides an overview of buprenorphine, including
information on side effects and interactions with other medications.
Pet Place also has some information about
buprenorphine (no need to register to read the article, just click on
Close at the bottom of the pop-up).
Fentanyl (Duragesic)
Fentanyl is also a narcotic belonging to the same drug
family as morphine. Therefore it is a very effective painkiller. It is
usually given in the form of a patch (like a plaster) on the skin which
slowly releases the medication for 4-5 days. Side
effects are uncommon and usually minor e.g. allergy to the patch adhesive.
The most common serious side effect (although it is still relatively rare)
is an adverse effect on breathing, which may manifest itself as lethargy.
Fortunately removing the patch should quickly resolve any problems.
Fentanyl should not be used in cats taking Anipryl for
cognitive
dysfunction. Heat can increase the amount of Fentanyl released, which
could be very dangerous, so access to heat (e.g. heated cat beds) should
be removed for any cat with a Fentanyl patch. Care should be taken to
ensure that the cat cannot remove the patch or lick it.
My Indie (non-CKD) had
extensive dental extractions, and was given a Fentanyl patch
to help her oral pain. The patch was applied to a small area of shaved
skin on one of her back legs, and lasted for several days. It worked very
well for her, she was a little subdued but that was the only side effect
(which might actually have been due to the after effects of the surgery).
However, up to a third of cats absorb less of the medication than is
needed for effective pain control, so be aware of the
signs of pain in cats so
you can ensure it is working properly for your cat.
Strictly speaking Tramadol is not an opiate but it has some effect on
opioid receptors, so I am including it in this category.
Tramadol is a safe treatment and side effects are rare, but include
sedation and constipation. It has been known to cause hallucinations and
seizures in humans so should be used with caution in cats with a history
of seizures. Unfortunately Tramadol tastes very bitter to cats.
Tramadol is available as a generic which means it is inexpensive. It is
commonly sold as a 50mg tablet, and is dosed at 1 to 2 mg/kg 2-3 times a
day, so a 10 lb (4.55kg) cat would receive 4.5 - 9mg 2-3 times a day. In
practice many people simply start with a quarter of a 50mg tablet (12.5mg)
twice a day. It is metabolised largely by the liver but around 30% is
excreted by the kidneys so your vet may wish to reduce the dose for a CKD
cat.
Mar Vista Vet has some information about
Tramadol. It
mentions that using
Tramadol at the same time as an appetite stimulant called
mirtazapine increases the risk of serotonin syndrome.
Non-steroidal anti-inflammatory drugs help reduce inflammation and
also offer some degree of pain control.
NSAIDs work by blocking prostaglandin production. They do this by binding
with enzymes called
cyclo-oxygenase (COX). There are two forms of COX, COX-1 and COX-2. COX-1
is protective, particularly in the kidneys and the digestive tract,
whereas COX-2 produces pain and inflammation. The goal is therefore to
reduce levels of COX-2 while not affecting COX-1, although even reducing
levels of COX-2 only does not entirely remove the risk of side effects.
Meloxicam (Metacam) is a COX-2 preferential NSAID, i.e. it works effectively on COX-2
to reduce pain and inflammation but also reduces levels of COX-1 to some
degree. Robenacoxib (Onsior) is a COX-2 selective NSAID, i.e. it works effectively on
COX-2 to reduce pain and inflammation but does not affect levels of COX-1.
NSAIDs are commonly used in human and canine medicine.
They can be very helpful for conditions such as
arthritis.
Unfortunately cats tend to metabolise them poorly, plus there is only
limited research into their longer term use in cats, so many vets are
reluctant to use these drugs in cats.
The Veterinary Anesthesia and Analgesia Support
Group says that "Extreme caution
should be exercised when employing NSAID’s in cats."
The most common side effects of NSAIDs seen in cats are kidney problems
and gastro-intestinal problems. Since CKD cats already have kidney
problems and often also have gastro-intestinal problems such as stomach
acid, NSAIDs are therefore not the best choice for CKD cats. However,
sometimes you may have to use them e.g. if your cat has severe
arthritis,
because ongoing pain is not acceptable.
NSAIDS should not be used at the same time as
corticosteroids.
Close monitoring is required if they are used in cats taking
ACE inhibitors
(e.g. Fortekor) or
diuretics
because using these treatments together increases the risk of kidney
problems.
ISFM and AAFP consensus guidelines: long-term use of
NSAIDs in cats (2010) Journal
of Feline Medicine and Surgery 12, pp521-538 is a paper by the
International Society of Feline Medicine and the American Association of
Feline Practitioners. On page 530 there is a box discussing the use of
NSAIDs in cats with renal disease. Boehringer-Ingelheim, the manufacturer
of Metacam, gave a grant to help facilitate the development of these
guidelines.
Effects of non-steroidal anti-inflammatory drugs
(NSAIDs) on renal function (2007)
Brown SA State of the Art in Renal Disease in Dogs and Cats Proceedings,
Vetoquinol Academia reports (page 31) on the use of NSAIDs in CKD. Dr
Brown states "It has long been known that NSAIDs have a good margin of
renal safety for short- term use in healthy animals. Unfortunately, we
often use them in aged animals with a variety of clinical or subclinical
conditions or in animals undergoing anesthesia and surgery. The study of
the effects of NSAIDs on the kidney shows that the COX-2 selective drugs
are not necessarily safer for the kidneys. In well hydrated otherwise
healthy cats with IRIS stages I and II Chronic Kidney Disease (CKD),
NSAIDs seem to be generally well tolerated.
Robenacoxib is a non-steroidal anti-inflammatory drug
(NSAID). It has been approved for use in cats in the UK
since 2009 for the treatment of acute pain and inflammation associated
with musculoskeletal disorders (e.g. arthritis) for up to six days. It was
approved for use in cats in the USA in April 2011. The US approval is to control post-operative
pain and inflammation, for which it can be used once daily for up to three
days.
Since robenacoxib is 30% excreted by the kidneys, it should be used with caution in cats with
CKD, who should be monitored closely. Do not use
robenacoxib at the same time
as steroids.
Close monitoring is required if it is used in cats taking
ACE inhibitors
(e.g. Fortekor) or
diuretics
because using these treatments together increases the risk of kidney
problems.
Aspirin is another NSAID. Aspirin can be toxic to cats, who can only
metabolise it very slowly, so it is not usually used as a painkiller in
cats, although it is occasionally used to
treat heart problems when the benefits outweigh the risks.
In such cases it is usually only given in very low doses once every three
days.
Meloxicam
is also a non-steroidal anti-inflammatory drug
(NSAID) available in both injectible and liquid
(oral) form. Although it is approved in the UK for the ongoing
treatment of arthritis in cats (and I myself used it successfully for my
PKD but
not CKD cat), there are concerns that it may cause kidney disease,
particularly when used at higher doses, as sometimes happens in the USA
where cat-sized doses are not available.
Meloxicam is a non-steroidal anti-inflammatory drug
(NSAID) available in both injectible and liquid
(oral) form. Under the name of Metacam it is approved for use in dogs in both
forms, but since cats tend to metabolise NSAIDs
very poorly, in the USA Metacam is only approved for use in cats
in its injectible form. This is because it is intended to be a one-off
treatment as a painkilling injection following surgery.
However, the injectible form has only been tested on cats given
one particular type of anaesthesia.
The situation was similar in Europe, where only the
injectible version of Metacam was approved for one-off use in cats following surgery.
This changed in June 2007 when the
oral form of Metacam was licensed for cats for longer term pain management
e.g. for use in cats with arthritis. This feline oral version of Metacam is
a 0.5mg/ml oral suspension compared to the canine version which is a
1.5mg/ml suspension. Another oral version of meloxicam for cats in the
same strength (0.5mg/ml) was introduced in the UK in 2011 under the name
of Meloxidyl.
In the USA, meloxicam also
appears to be being used more and more frequently off-label for
cats in its liquid (oral) form on an ongoing basis, but
because there is no feline version available, vets are using the canine
version, theoretically at reduced doses. However, since meloxicam is often
dosed in drops rather than precise measurements, this may lead to
overdosing.
Unfortunately meloxicam may be
nephrotoxic, i.e. toxic to the kidneys. In fact, it
may in some cases
cause permanent damage to the kidneys (papillary necrosis), with the
result that a number of cats seem to have developed acute kidney
injury or
chronic kidney disease after taking meloxicam.
Retrospective case-control study of the effects of long-term dosing with
meloxicam on renal function in aged cats with degenerative joint disease
(2011) Gowan RA, Lingard AE, Johnston L, Stansen W, Brown SA, Malik R
Journal of Feline Medicine & Surgery13(10) pp752-761
retrospectively examined the records of a veterinary practice over a five
year period and concluded that "long-term therapy with meloxicam at a
median dose of 0.02 mg/kg/day can be administered safely to aged cats with
CKD, provided they are clinically stable. The results further suggest that
meloxicam may actually slow the progression of renal disease in cats with
both DJD andCKDby direct or indirect mechanisms." The study goes on to
speculate that meloxicam might slow the progression of CKD by reducing
proteinuria (recent studies indicate that medications in the same family
as meloxicam can reduce proteinuria in humans and rats).
Nevertheless, in October 2010 the
US Food & Drug Administration announced
that a "black box warning" would be added to meloxicam products, which
states: "Warning. Repeated use of meloxicam in cats has been
associated with acute renal failure and death. Do not administer
additional injectable or oral meloxicam to cats. See contraindications,
warnings and precautions for detailed information."
Meloxicam Dosing
It appears that the dosing
used is critical. In the USA, since the feline form of meloxicam is not
available, vets have to use the three times as strong canine form, and it
may be that they are not adjusting the dose appropriately for cats,
especially if they give it in drops (Metacam comes with a dropper
dispenser) directly into the cat's mouth rather than measuring it out in
mg first. The Dear Doctor letter states: "Metacam
Oral Suspension is not licensed in the U.S. for use in cats. Unfortunately
adverse events in cats do occur. These have been reported at a consistent
level over the past 5 years and the majority following the inappropriate
off-label administration of the more concentrated 1.5 mg/mL formulation in
cats."
It also appears to be riskier if a cat is given injectible meloxicam
followed by the oral form.
Freedom of Information Summary(2004) from the US Food and Drug Administration concludes: "Meloxicam,
when initially dosed as a subcutaneous injection followed by oral dosing
for nine days at > 0.3 mg/kg was associated with severe adverse
effects, including death."
The National Office of Animal Health
explains more about the recommended dose for cats in the UK. The usual
dose of the 0.5 mg/ml strength of oral meloxicam is as follows (a kg is 2.2 lbs):
0.1mg/kg for the first dose;
0.05mg/kg for subsequent doses given once a day;
the oral form should not be given after using the
injectible form.
thereafter 0.025 mg/kg
every 48 to 72 hours. For accurate dosing use TB or insulin syringe
minus needle.
Robertson VCNA Protocol (SAP 2008)
0.05 mg/kg on the first day
0.025 mg/kg every 24 hours or less (titrate to lowest
effective dose.
Gunew et al Protocol (FMS 2008)
0.01-0.03 mg/kg once daily.
this is the protocol used in the above study.
We did use
meloxicam for Harpsie when his arthritis flared up acutely in 2004 following
a fall off a sofa while we were out and he was in dreadful pain which
other pain medications did not seem to help (he was literally screaming). It worked very well and caused no long term problems for him,
but since Harpsie had PKD, we only
used it at a very low dose, and much less frequently than normally
recommended, and it still controlled the pain effectively.
We checked his kidney values a month later (they were fine).
Although
meloxicam is very effective at controlling pain, I would not recommend its
use in a cat who already has CKD. Nor does the UK
National Office of Animal Health, which
states "Do not use in animals suffering from gastro-intestinal
disorders such as irritation and haemorrhage, impaired hepatic, cardiac or
renal function and haemorrhagic disorders".
However, in
Effects of non-steroidal anti-inflammatory drugs
(NSAIDs) on renal function (2007)
Brown SA State of the Art in Renal Disease in Dogs and Cats Proceedings,
Vetoquinol Academia, Dr Brown states on page 31 "In well hydrated
otherwise healthy cats with IRIS stages I and II Chronic Kidney Disease
(CKD), NSAIDs seem to be generally well tolerated." He recommends close
monitoring, avoiding dehydration or low blood pressure, and not using for
more than ten days.
If you choose to use meloxicam in a cat without CKD, I would use a lower
dose than is usually recommended.
If you do use meloxicam and your cat develops kidney
disease,
please see
below
for information on how best to treat it, and how to report it to the
authorities.
Meloxicam may
interact with
ACE inhibitors
such as benazepril (Fortekor or Lotensin) or
enalapril (Enacard) so do not give both medications to your cat
without checking with your vet first.
Metacam Package Insert for Cats (NADA141-219)
relates to the injectible form of Metacam in the USA. It now carries a
"black box warning" as required by the FDA which states: "Warning.
Repeated use of meloxicam in cats has been associated with acute renal
failure and death. Do not administer additional injectable or oral
meloxicam to cats. See contraindications, warnings and precautions for
detailed information."
The Metacam Professional Insert
(NASA 141-213) for the oral
suspension version of Metacam, approved
by the US Food and Drug Administration, states (page 2): "renal failure
has been reported as an outcome of repeated oral dosing of cats".
Freedom of Information Summary(2004)
from the US Food and Drug Administration mentions on page 23 that,
following the use of Metacam for post-operative pain, 8.3% of the cats in
the study had elevated
BUN levels, and 12.5% had
anaemia. In comparison, there were no cases of elevated BUN levels in
cats in the study given another post-operative painkiller, although 6.1%
of them did have anaemia (one possible cause of anaemia is inflammation,
which may partly explain this finding). The paper concludes: "Meloxicam,
when initially dosed as a subcutaneous injection followed by oral dosing
for nine days at > 0.3 mg/kg was associated with severe adverse
effects, including death."
The US Food and Drug
Administration
reprimanded the manufacturers of Metacam in 2004
for misleading claims for the product and omission of important safety
information.
The European Medicines Agency states
(P36) "do not use in animals suffering from gastrointestinal disorders
such as irritation and haemorrhage, impaired hepatic, cardiac or renal
function." It also says (P103) that the use of
Metacam should be avoided in dehydrated animals "as there is a potential
risk of renal toxicity", and warns that the oral
form of Metacam should not be used following use of the injectible form.
Pet
Placestates "Meloxicam can
adversely affect kidney function by causing sudden severe injury to the
kidneys (papillary necrosis)."
Mar Vista Vet also has some information
about meloxicam and recommends avoiding its use in cats with kidney, liver
or heart disease, as well as in cats who are dehydrated or who have
stomach ulcers.
Provet
has some warnings about the use of meloxicam.
Metacam
UK is the manufacturer's British website about the use of meloxicam
in dogs. It mentions the recent approval of the
drug for ongoing use in cats, but has very little information about this.
Metacam USA is the manufacturer's American website about the use of Metacam in
dogs.
Dealing with
Adverse Reactions to Meloxicam
If you believe your cat has developed kidney disease as
a result of using meloxicam in the form of Metacam, you should report
this to the manufacturers. The number to call in the USA is 1-866-METACAM
(638-2226). You will probably find yourself speaking
to a Dr Carey or a Dr Grubb, who should work with your vet to devise a
treatment
plan.
Most cats who suffer kidney disease as a result of using
Metacam are suffering from
acute kidney
injury (AKI) and their bloodwork
may be extremely high, with creatinine often in the high teens. Do not
give up hope! Acute kidney injury is difficult to treat, but not
impossible: an aggressive treatment plan should see those numbers
dramatically reduce in most cases, and in some cases a complete recovery
from a case of acute kidney injury is possible. In fact, one person was
told by the manufacturer that 77% of cats affected by Metacam make a full
recovery with prompt and proper treatment, so don't opt for euthanasia
immediately. However, I understand that the manufacturer considers a
creatinine in the 3s to indicate that the cat is stabilised, and whilst
this is certainly not a critical level nor grounds for euthanasia, it does
indicate some residual kidney damage.
A treatment programme which includes 4-5 days of IV
fluid therapy (hospitalisation), followed by 4-6 weeks of sub-Q fluids at
home, is often recommended by the manufacturers, but talk to them and see
what they suggest for your cat. I would also suggest that you ask the
manufacturers to pay your veterinary costs - I know they have done this
for some people, although they have not necessarily paid the full costs.
It would appear that they may pay more if your vet calls.
If you are in the USA, you should also make a report to the Food & Drug
Administration. Apparently the manufacturers are not obliged to report any
cases of kidney problems to the FDA because renal failure is already listed
in the package insert as a possible side effect (see the second link
above),but I believe it is very important for the FDA to be fully aware
of the scale of the problem.
FDA Consumer Complaints Co-ordinator has details of the relevant contacts for each state.
Gabapentin is an anti-convulsant (used to prevent seizures) but may help
with pain, particularly arthitic or neuropathic pain. It may cause sedation.
It may be risky to give anti-seizure medication to a cat who has never had
a seizure.
Gabapentin is excreted via the kidneys so the dose should be reduced for
CKD patients, who need close monitoring while on the drug. Gabapentin
should not be stopped suddenly but gradually tapered down.
Paracetamol (UK) or acetaminophen or Tylenol (USA) is toxic to cats, with a
very narrow safety margin, so even a tiny dose can be extremely dangerous.
Please never give your cat paracetamol/acetaminophen.
